The present invention disclosed herein relates to a method and an apparatus for processing an optical signal of a spectrometer using sparse nature of a signal spectrum, and more particularly, to a method and an apparatus for processing an optical signal of a spectrometer using sparse nature of a signal spectrum in which high resolution can be achieved by finding unknown spectrum information based on previously known spectrum information using a digital signal processing (DSP) technique, even with to a small number of filters in an optical filter array compared to an optical wavelength band.
A spectrometer is used as an essential instrument in various industrial fields of optics, chemistry, oceanics, and the like. The spectrometer measures intensities at various wavelengths of light from an object and shows the same in graph or a spectrum form. A degree of how precisely the spectrometer shows spectral information about an object is called resolution.
A small spectrometer among the spectrometers adopts a filter array in order to reduce cost. The filter array indicates a structure produced with filters intensively arranged at one point.
A filter array technique adopting a nano process can minimize a size of the spectrometer, thereby enabling mass production and production cost reduction. A small spectrometer produced by this process is greatly helpful in measuring feature of an object in the industrial field outside the laboratory. The small spectrometer can also be used in easy connection with a computer or other electronic devices. In addition, a filter array based spectrometer has an advantage of measuring spectrum information of an optical source in a short time.
Since the limit of resolution in the spectrometer is determined by the number of filters in the optical filter array, however, it is necessary to increase the number of filters or develop a new device for increasing the resolution.
In the small spectrometer, there occur problems that the spectrum information is distorted due to reductions in the number of filters on which the resolution depends. Accordingly the spectrum information obtained from the spectrometer gets significantly distorted so that the original spectrum information of the optical signal cannot be accurately obtained.